1. Chapter 3 IN PEARSON book
Welcome to Ecology!
Chapter 3 IN PEARSON book
“The trouble with ecology is that you never know where to start because every thing affects everything else.” – Robert Heinlein “Farmer in the Sky”

2. Biological Sciences Earth Sciences Physical Sciences Ecology
Ecology is an interdisciplinary science
Ecological studies are done at the interface of these 3 fields
“As an area of scientific study, ecology incorporates the hypothetico-deductive approach, using observations and experiments to test hypothetical explanations of ecological phenomena… ecologists face extraordinary challenges in their research because of the complexity of their questions, the diversity of their subjects and the large expanse of time and space over which studies must be conducted. Ecological questions from a continuum with those from other areas of biology, including genetics, evolution, physiology and behavior, as well as those from other sciences, such as chemistry, physics, geology and meteorology. “

3. Brainstorm session
What does “bio” mean? What does “eco” mean? What do you think we are going to study in ecology? What were some examples of ecology concepts in the movie: The Future of Food?

4. Ecology O2
Nutrients
CO2
Ecology is the study of the relationships between organisms and their physical and biotic environment:
“Organisms respond to their environments and can also change their environments, producing and ever changing, dynamic biosphere”. – pg 65

5. Learning Goals for this Unit
Recognizing the various levels of ecological organization
Explain matter and energy’s interdependence in nature.
Understanding how organisms get the energy the need to survive; looking at food chains and food webs
Describing how nutrient availability relates to the primary productivity
Understanding a producers means of obtaining energy through photosynthesis
Explaining how ATP is useful in cells

6. Ecological Levels of Organization
Living organisms can be studied at different levels of complexity.
From least to most complex, these levels are (in an ecological context):
Individual
Population
Community
Ecosystem
Biome
Biosphere
Biosphere
Biome
Ecosystem
Community
Population
Individual

7. Biosphere
Biosphere
Ecosystems
Communities
Populations
Organisms

8. First Level:
Organism: A living thing.

9. Second Level:
Population: A group of organisms, all of the SAME SPECIES

10. Third Level:
Community: Made up of different species living in the same place at the same time.

11. Fourth Level:
Ecosystem: Made up of different species AND the abiotic factors of that habitat

12. Fifth Level
Biome: A group of ecosystems that share similar climates and types of organisms. (biomes share similar climates – “B before C”)

13. Sixth Level: The Biosphere
The biosphere is the region within which all living things are found on Earth.
It is the narrow belt around the Earth extending from the bottom of the oceans to the upper atmosphere.

14. What level of Organization?
Population

15. What level of Organization?
A community is a naturally occurring group of organisms living together as an ecological entity; the biological part of the ecosystem.
A nudibranch snail feeding on rock encrusting organisms

16. What level of organization?
Organism

17. What level of Organization?
Ecosystem

18. Components of an Ecosystem
An ecosystem encompasses the physical environment and the community.
Community
Physical environment

19. Ecosystem Physical environment Community Abiotic factors
atmosphere, soil, water,
wind speed wind direction, current velocity
Biotic factors
competitors, symbionts, predators, parasites, pathogens
Physical environment
Community

20. Light intensity varies
Ecosystems
Light intensity varies
Flow rate varies
Rainfall level varies
Fast flowing water habitat
Still water habitat
An ecosystem includes:
all of the organisms (the community) …
and their physical environment.
There are many different sorts of ecosystems from natural to artificial, and they range in size from large to small.
Rock habitat
Stream bank habitat

21. What level of Organization?
Population

22. A Hierarchy of Interactions
Ecology can be divided into four increasingly comprehensive levels
Organismal ecology
Population ecology
Community ecology
Ecosystem ecology

23. Hierarchy of Interactions:

24. Organismal Ecology
Is concerned with the evolutionary adaptations that enable individual organisms to meet the challenges posed by their abiotic environments
Figure 18.4a

25. Population Ecology
Is concerned with populations, groups of individuals of the same species living in the same area
Concentrates mainly on factors that affect population density and growth
Figure 18.4b

26. Community Ecology
Is concerned with communities, assemblages of populations of different species
Focuses on how interactions between species affect community structure and organization
Figure 18.4c

27. Ecosystem Ecology
Is concerned with ecosystems, which include all the abiotic factors in addition to the community of species in a certain area
Focuses on energy flow and the cycling of chemicals among the various abiotic and biotic factors
Figure 18.4d

28. Ecology vs. Environmental Science
The science of ecology can provide understanding behind some environmental problems or concerns BUT does not involve the decision making process on solving those problems.
Doesn’t include: politics, economics, and ethical views to environmental problems
Example: Global climate change
ECOLOGY INVOLVED: how animals change to adapt to different changes in climate
OTHER FACTORS: How have humans influenced this change in climate and what can we do to slow change?

29. Two environmental components when studying ecology:
ABIOTIC FACTORS:
BIOTIC FACTORS:

30. Abiotic or Biotic?
Biotic

31. Abiotic or Biotic?
Abiotic

32. Abiotic or Biotic?
Abiotic

33. Abiotic factors to consider:
Sunlight
Solar energy powers nearly all ecosystems
Water
Aquatic organisms face problems with water vs salt ions balance
Terrestrial organisms main water problem is dessication
Wind
Organisms such as plants depend on wind to disperse pollen and seeds (or nutrients blown to them).
Temperature
It’s effect on an organisms metabolism

34. Environments
The physical environment refers to the physical surroundings of any organism, including:
the medium, e.g. water
substrate, e.g. soil
climatic (atmospheric) conditions
light …
and other physical properties.

35. What is the connection between abiotic factors and distribution of species (biotic)?
Range of tolerance
Every organism/population thrives in an optimal range of abiotic factors
Outside of this range, less numbers of the organism
Figure 18.8

36. Abundance of organisms
Population size
Low
High
Temperature
Zone of
intolerance
physiological stress
Optimum range No
organisms
Few
Lower limit
of tolerance
Abundance of organisms
Upper limit

37. Energy, Producers, and Consumers
When do you use energy?
Energy, Producers, and Consumers

38. Primary Producers
AUTOTROPHS
plants, certain bacteria, & algae

39. Where do Primary Producers get their energy?
CHEMOSYNTHESIS
Discovered 35 yrs ago when investigating volcanic vents in total darkness.
PHOTOSYNTHESIS